let X be non empty set ; for R being connected total Relation of X
for x, y being Element of X holds
( not x <> y or x,y in R or y,x in R )
let R be connected total Relation of X; for x, y being Element of X holds
( not x <> y or x,y in R or y,x in R )
let x, y be Element of X; ( not x <> y or x,y in R or y,x in R )
field R = X
by ORDERS_1:12;
then
( not x <> y or [x,y] in R or [y,x] in R )
by RELAT_2:def 6, RELAT_2:def 14;
hence
( not x <> y or x,y in R or y,x in R )
; verum